Abstract: An electronic apparatus performs a method of decoding video data, including receiving, from bitstream, a first syntax element in a slice header of a slice that indicates whether luma mapping with chroma scaling (LMCS) is applied to a coding unit in the slice; receiving a second syntax element for the coding unit that indicates whether the coding unit has been coded using adaptive color-space transform (ACT); if the second syntax element has a non-zero value, decoding the coding unit by applying inverse ACT to convert luma and chroma residuals of the coding unit from a transformed color space to an original color space of the video data; and if the first syntax element has a non-zero value, decoding the coding unit by performing inverse luma mapping to the luma samples and inverse scaling to the chroma residuals of the coding unit after performing the inverse ACT.

Abstract: An electronic apparatus performs a method of decoding video data, including receiving, from bitstream, a first syntax element in a slice header of a slice that indicates whether luma mapping with chroma scaling (LMCS) is applied to a coding unit in the slice; receiving a second syntax element for the coding unit that indicates whether the coding unit has been coded using adaptive color-space transform (ACT); if the second syntax element has a non-zero value, decoding the coding unit by applying inverse ACT to convert luma and chroma residuals of the coding unit from a transformed color space to an original color space of the video data; and if the first syntax element has a non-zero value, decoding the coding unit by performing inverse luma mapping to the luma samples and inverse scaling to the chroma residuals of the coding unit after performing the inverse ACT.

Abstract: Methods for video decoding and encoding, apparatuses and non-transitory storage media are provided. In one decoding method, the decoder obtains a first candidate position and a second candidate position. The decoder obtains a third candidate position based on the first and second candidate positions and obtains a virtual block based on the first, the second, and the third candidate positions. The decoder may obtain a plurality of CPMVs for the virtual block based on translational MVs at the first, second, and third candidate positions; and project, the plurality of CPMVs for the virtual block to a current block to obtain a translational MV based on a specific position within the current block or a second plurality of CPMVs for the current block.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for decoding a video signal. A method may include obtain a first reference picture and a second reference picture associated with a video block, wherein the first reference picture is before a current picture and the second reference picture is after the current picture in display order; obtain first prediction samples of the video block from the first reference picture; obtain second prediction samples of the video block from the second reference picture; obtain padded prediction samples, and obtain horizontal and vertical gradient values of the first prediction samples and the second prediction samples based on the padded prediction samples; obtain motion refinements for samples in the video block based on the horizontal and vertical gradient values; and obtain bi-prediction samples of the video block based on the motion refinements.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for video coding. In one method, a decoder obtains a first signaled flag that indicates whether a template-based intra mode derivation (TIMD) mode is applied on a current video block; and in response to determining that the TIMD mode is applied on the current video block based on the first signaled flag, the decoder obtains a second signaled flag in transform block (TB), coding block (CB), slice, picture, or sequence level that indicates whether signaling of an index of a template for TIMD is enabled, where the index of the template is signaled to derive the intra prediction mode for the current video block.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for coding a video signal. A method includes obtaining a first reference picture and a second reference picture associated with a video block; obtaining first prediction samples of the video block from the first reference picture; obtaining second prediction samples of the video block from the second reference picture; obtaining padded prediction samples, and obtaining horizontal and vertical gradient values of the first prediction samples and the second prediction samples based on the padded prediction samples; obtaining motion refinements for samples in the video block based on the horizontal and vertical gradient values; and obtaining bi-prediction samples of the video block based on the motion refinements.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for encoding a video signal. A method may include obtain a first reference picture and a second reference picture associated with a video block, wherein the first reference picture is before a current picture and the second reference picture is after the current picture in display order; obtain first prediction samples of the video block from the first reference picture; obtain second prediction samples of the video block from the second reference picture; obtain padded prediction samples; obtain horizontal and vertical gradient values of the first prediction samples and the second prediction samples based on the padded prediction samples; obtain motion refinements for samples in the video block based on the horizontal and vertical gradient values; and obtain bi-prediction samples of the video block based on the motion refinements.

Abstract: Methods for video decoding and encoding, apparatuses and non-transitory computer-readable storage media thereof are provided. In one method for video decoding, a binary arithmetic decoder may obtain, according to an adaptive weight, a multi-hypothesis probability for a binary symbol of a context model for the binary arithmetic decoder, where the multi-hypothesis probability indicates a probability of the binary symbol equaling to a binary value, and the binary symbol is from a plurality of binary symbols associated with the context model. Furthermore, the decoder may decode the binary symbol according to the multi-hypothesis probability.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for encoding a video signal. A method may include obtain a first reference picture associated with a video block in a current picture within the video signal and a first motion vector (MV) from the video block in the current picture to a reference block in the first reference picture; obtain first prediction samples I(i,j) of the video block generated from the reference block in the first reference picture; control internal bit-depths of internal prediction refinement with optical flow (PROF) parameters; obtain a prediction refinement value for the first prediction sample I(i,j); obtain second prediction samples I?(i,j) associated with a second MV and a corresponding prediction refinement value for a second prediction sample I?(i,j); and obtain a final prediction sample of the video block based on the first prediction sample I(i,j), the second prediction sample I?(i,j), and the prediction refinement values.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for encoding a video signal.

Abstract: An electronic apparatus performs a method for video decoding. The method comprises: receiving, from a bitstream, a coding unit and determining a mode type condition of the coding unit; if the coding unit is encoded in a first chroma format, setting the mode type condition of the coding unit to a first mode type condition; if the coding unit is encoded in a second chroma format and the coding unit is a smallest chroma intra prediction unit, setting the mode type condition of the coding unit to a second mode type condition if a luma block of the coding unit and the splitting method satisfy a first criterion; setting the mode type condition of the coding unit to a third mode type condition if the luma block of the coding unit and the splitting method satisfy a second criterion, and decoding the coding unit based on the mode type condition.

Abstract: An electronic apparatus performs a method for video decoding. The method comprises: receiving, from a bitstream, a coding unit and determining a mode type condition of the coding unit; if the coding unit is encoded in a first chroma format, setting the mode type condition of the coding unit to a first mode type condition; if the coding unit is encoded in a second chroma format and the coding unit is a smallest chroma intra prediction unit, setting the mode type condition of the coding unit to a second mode type condition if a luma block of the coding unit and the splitting method satisfy a first criterion; setting the mode type condition of the coding unit to a third mode type condition if the luma block of the coding unit and the splitting method satisfy a second criterion, and decoding the coding unit based on the mode type condition.

Abstract: Methods, devices, and storage mediums are provided for decoding video signals. A decoder receives at least one versatile video coding (VVC) syntax flag. The decoder receives, in response to a syntax element indicating that inter prediction is allowed, inter related syntax elements. The decoder obtains a first reference picture I(0) and a second reference picture I(1) associated with a video block in a bitstream. The decoder obtains first prediction samples I(0)(i,j) of the video block from a reference block in the first reference picture I(0). The decoder obtains second prediction samples I(1)(i,j) of the video block from a reference block in the second reference picture I(1). The decoder obtains bi-prediction samples based on the at least one VVC syntax flag, the inter related syntax elements, the first prediction samples I(0)(i,j), and the second prediction samples I(1)(i,j).

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from a bitstream, a first control flag that indicates merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence; receiving a first syntax from the video data that identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets; receiving, a second control flag corresponding to a respective coding unit of the one or more coding units, which indicates the MMVD is applied to the coding unit; receiving a second syntax that selects an MVD offset from the identified set of MVD offsets, and a third syntax that selects an MVD direction; forming MVD based on the selected MVD offset and MVD direction; and reconstructing the coding unit by applying the formed MVD to generate motion vectors to the coding unit.

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from a bitstream, a first control flag that indicates merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence; receiving a first syntax from the video data that identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets; receiving, a second control flag corresponding to a respective coding unit of the one or more coding units, which indicates the MMVD is applied to the coding unit; receiving a second syntax that selects an MVD offset from the identified set of MVD offsets, and a third syntax that selects an MVD direction; forming MVD based on the selected MVD offset and MVD direction; and reconstructing the coding unit by applying the formed MVD to generate motion vectors to the coding unit.

Abstract: A computing device performs a method of decoding video data by receiving a bitstream corresponding to video data encoding one or more pictures, wherein the one or more pictures are recursively partitioned into a plurality of groups at different partition levels; determining a first syntax element that corresponds to a first group of the plurality of groups; in accordance with a determination that the first syntax element has a first value: decoding the first group in a first mode and in accordance with a determination that the first syntax element has a second value: determining a respective second syntax element for each of one or more second groups within the first groups, wherein the one or more second groups are at a second partition level below the first partition level and decoding each of the one or more second groups in accordance with a value of the respective second syntax element.

Abstract: The present disclosure provides a method for decoding video data. The method comprises: obtaining a video block of the video data from a bitstream; classifying a luma sample corresponding to a chroma sample of the video block into one of a plurality of sample groups based on edge information of the luma sample, wherein the luma sample is obtained from one or more of luma samples of the video block; and predicting the chroma sample by applying one of a plurality of linear prediction models corresponding to the classified sample group to the luma sample.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for video coding. In one method, a decoder obtains a signaled flag that indicates whether a template-based intra mode derivation (TIMD) mode is applied on a current video block; and in response to determining that the TIMD mode is applied on the current video block based on the signaled flag, the decoder derives an intra prediction mode from the TIMD mode based on different templates in a reconstruction area for the current video block, wherein the reconstruction area comprises reconstructed neighboring blocks for the current video block.

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from a bitstream, a first control flag that indicates merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence; receiving a first syntax from the video data that identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets; receiving, a second control flag corresponding to a respective coding unit of the one or more coding units, which indicates the MMVD is applied to the coding unit; receiving a second syntax that selects an MVD offset from the identified set of MVD offsets, and a third syntax that selects an MVD direction; forming MVD based on the selected MVD offset and MVD direction; and reconstructing the coding unit by applying the formed MVD to generate motion vectors to the coding unit.

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from the bitstream, a plurality of syntax elements associated with a coding unit, wherein the plurality of syntax elements indicate the coding tree type of the coding unit, and whether the local dual tree mode is enabled for the coding unit; and in accordance with the determination that the coding tree type of the coding unit is a single tree, and the local dual tree mode is enabled for the coding unit: disabling the palette mode for the coding unit when the coding unit has the size equal to or less than a predefined threshold. In some embodiments, disabling palette mode for the coding unit includes: disabling the palette mode for both the luma component and chroma component of the coding unit, or disabling the palette mode for only the chroma component of the coding unit.